This is Humphry Davy, the scientist who invented the Davy lamp. He also discovered laughing gas! He experemented with gasses by inhaling them. The Davy lamp was a lamp used by coal miners! This lamp prevented the gasses in the air from exploding in the coal mine. This allowed coal miners to have light in the mine without exploding.
Humphry Davy created the Davy lamp (He named it after himself =D). This lamp was a encased candle in a metal case. It had a glass case around the candle so it still provided light. This prevented the gasses in the air from exploding. An open flame candle would make the gasses explode, so this lamp was the only lightsource they could use.